本論文應用光學技術及影像處理演算法進行BGA量測及缺陷的檢測。先由數位顯微鏡擷取影像，經過灰階、中值濾波、二值化、形態學和邊緣特徵處理，將原始含有雜訊的圖片濾波去除雜訊和影像加強後，將我們所需要的特徵留下且增強。藉著點到點的距離公式算出錫球的半徑，用來判斷BGA上每顆錫球的半徑尺寸是否過大或過小，由於每家公司對於容忍誤差的範圍皆不同，所以本論文採用三種不同的容忍誤差來實現，容忍誤差分別是2%、3%、和4%。目前很少關於錫球表面上凹陷的研究，本論文提出了一種新的判別錫球凹陷的方法。由於本實驗用穩壓器加上可變電阻來調整LED光源的亮度，所以造成有凹陷的錫球和沒凹陷的錫球在LED的照明下有明顯的不同，本論文就利用這個特徵來判別錫球是否有凹陷。
最後的實驗結果，本系統可進行多球、少球、過大、過小和凹陷的檢測，能有效的檢測BGA產品。

This thesis applied optical detection and image processing to perform BGA (Ball Grid Array) measurement and inspection. An image is firstly obtained from a digital microscope, then features remaining from gray-scale, median filter, binarization, morphology and edge detection are enhanced. Following this, noise from the original image are removed and desired features enhanced. Through a formula which includes distance from one point to another, radii of solder balls can be obtained, from which the size of solder balls can be determined as either oversized, undersized, or not. Because every factory has its own individual error tolerance, this thesis used three implementation principles, where the three tolerant errors are 2%, 3%, and 4%, respectively. There are several studies concerning BGA inspection, but only few attempts have so far been made at dimples of solder balls. We developed a new approach to inspect the dimples of solder balls. This experiment adjusts the brightness of light by a voltage regulator and variable resistor circuit. Balls with dimples and those without appear differently in LED light; as such, this thesis used this feature to determine whether or not there is a dimple on the surface of solder balls.
Overall, results of this experiment can offer detection for the radii of solder balls, extra balls, missing balls, oversize, undersize, and dimples of solder balls, and can also provide effective inspection of the BGA product.

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